package com.cs.netty.http;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.http.*;
import io.netty.util.CharsetUtil;

import java.net.URI;

/**
 * @ClassName: TestHttpServerHandler
 *
 * 1. SimpleChannelInboundHandler 是 ChannelInboundHandlerAdapter 子类
 * 2. HttpObject 客户端和服务端相互通讯的数据被封装成 HttpObject
 *
 * @Description: TODO
 * @Author: kevin
 * @Date: 2020/8/11 15:53
 * @Version: 1.0
 */
public class TestHttpServerHandler extends SimpleChannelInboundHandler<HttpObject> {

    /**
     * 读取客户端的数据
     *
     * @param ctx
     * @param msg
     * @throws Exception
     */
    @Override
    protected void channelRead0(ChannelHandlerContext ctx, HttpObject msg) throws Exception {

        System.out.println("对应的channel=" + ctx.channel() + " pipeline=" + ctx.pipeline() +
                " 通过pipeline获取channel" + ctx.pipeline().channel());

        System.out.println("当前ctx的handler=" + ctx.handler());

        // 判断 msg 是不是 HttpRequest 请求
        if (msg instanceof HttpRequest) {

            System.out.println("pipeline hashcode" + ctx.pipeline().hashCode() + " TestHttpServerHandler hash=" + this.hashCode());

            System.out.println("msg 类型=" + msg.getClass());
            System.out.println("客户端地址" + ctx.channel().remoteAddress());

            // 获取到
            HttpRequest httpRequest = (HttpRequest) msg;
            // 获取Uri, 过滤指定资源
            URI uri = new URI(httpRequest.uri());
            if ("/favicon.ico".equals(uri.getPath())) {
                System.out.println("请求了 favicon.ico, 不做响应");
                return;
            }

            // 回复信息给浏览器[http协议]
            ByteBuf content = Unpooled.copiedBuffer("hello, 我是服务器", CharsetUtil.UTF_8);

            // 构造一个 http 响应， 即 HttpResponse
            FullHttpResponse response = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.OK, content);

            response.headers().set(HttpHeaderNames.CONTENT_TYPE, "text/plain;charset=UTF-8");
            response.headers().set(HttpHeaderNames.CONTENT_LENGTH, content.readableBytes());

            // 将构建好的 response 返回
            ctx.writeAndFlush(response);

        }
    }
}
